In the modern society, people tend to have thickened and hardened blood vessel walls and accordingly suffer from cardiovascular disease because they usually intake too much high protein and cholesterol in their diets and lack of exercises. The blood vessel walls would also become thicker and hardened to cause cardiovascular disease when a person is getting old and has slowed metabolism. Moreover, some diseases having connection with metabolism and blood circulation, such as acute myocardial infarction and stroke, also have relation to hardened blood vessels.
The currently available medical technology can not thin or soften the thickened and hardened blood vessel walls. However, taking proper exercises is one of the ways to improve the cardiovascular disease. A man, when taking strenuous exercises, will have increased heartbeat higher than 120 and sweat heavily due to compressed muscles. At this point, toxins in the body, such as lipid peroxide in the blood vessel walls, will be discharged from the body via capillaries and sweat glands along with sweat. The removal of toxins from a man's body is health-beneficial to the gradual softening of blood vessel walls again. However, the strenuous exercises are not suitable for the aged and some disabled who are not able to conveniently move alone. Under this condition, the aged and the disabled tend to become weaker and weaker because the toxins in their bodies could not be duly discharged along with sweat. For people to sweat heavily even if they do not take exercises, steam bath has been introduced into people's daily life.
While the heat energy from the steam bath could forcefully compress and permeate a man's skin, it can only reach at the striae and the interstitial space in skin. The sweat given off the body under this condition is normally referred to as “surface-layer sweat” or “cold sweat”. U.S. Pat. No. 3,092,843 discloses a portable steam chest for steam bath, with which a user can give off the surface-layer sweat due to the steam heat.
U.S. Pat. No. 6,327,720 discloses a sauna made with illite surfaces, which is also a device for steam bath and uses illite to release far infrared rays, so that heat can more easily penetrate into the user's body to promote blood circulation.
The main functions that can be achieved with the steam bath provided by the portable steam chest disclosed in U.S. Pat. No. 3,092,843 include cleaning pores on skin and giving off sweat. On the other hand, the functions that can be achieved with the steam bath provided by the sauna made with illite surfaces disclosed in U.S. Pat. No. 6,327,720 include not only the cleaning pores and sweating, but also permeation of far infrared rays into skin to produce a health-beneficial hyperthermia effect.